South Dakota Native Plant Research
Fabaceae : Apios americana

Fabaceae : Apios americana


Download Seedling: Groundnut seedling grown in research greenhouse at SDSU. (82 KB)

Download Vegetative: The leaflets are 1.8-7 cm wide and 2-10 cm long. (738 KB)

Download Flowering: Flowers of wild potato in Brookings, S.D., in July. (1000 KB)

Download Legume (416 KB)

Family Name


Common Name

American potato bean, groundnut


Apios americana is a perennial herbaceous vine growing from slender rhizomes that produce tubers that get up 6 cm in diameter. The stems grow to 5 m long and climb or sprawl over shrubs and trees. The compound pinnate leaves are inserted in an alternate pattern, having deciduous stipules that are 5-7 mm long. The leaves usually have 5-7 leaflets that are ovate to lance-ovate and rounded at the base, with petioles that are 1.5-8 cm long. Flowers are organized in racemes that have a short peduncle (2-5 cm long) and are found in the axils of leaves. The calices are tubular with the lower lobe triangular and up to halve as long as the tube. The corolla is papilionaceous 10-14 mm long, with the banner reflexed, whitish dorsally and reddish ventrally. The wings are brown to purple, downcurved, and the keel is reddish brown. There are 10 diadelphous stamens, and the legume is straight to slightly curved 5-50 mm by 4-6 mm.

Additional Notes

One of the most attractive vines around, collected in both east and west river in South Dakota. Ground nuts do well in partial shade, especially where they receive morning sun and are protected during the afternoon. They do best in moist, mulched soil and can grow to 3 m in length. They produce a profusion of flowers in late July to August. They are easily propagated using the tubers. The vines can be aggressive if you don’t control their number by harvesting tubers in the fall. The tubers are high in protein and starch and can be prepared much like sweet potatoes.

Horticulture Notes

Seed Collection: Collect seed in August-October

Germination: Stratification of seeds – easiest to plant out in the fall or carefully chip the seed coat before planting in the spring.

Vegetative Propagation: Division of the tubers in the spring or autumn

Soils: Sandy and well-drained

Light: Full sun to partial shade.

Water: Dry to moist conditions

Fabaceae : Apios americana